Currently as you know that there are projects with OpenWRT on ARM.
Besides that from buildroot you can choose a wide range of ARM MPU, to build a new distribution, there are also some commercial SoC projects like this.
Well! Do you can virtualize these images with similar features and good performance?
Sure! The performance is decided by the host machine and also the available network hardware.
For the software there are several network-bridge strategy allowing Qemu virtualization have almost every feature you can find inside a dedicated hardware.
Here another link about a good implementation of these network-bridges on Qemu.
i'm mastering OpenWRT already, I'm not interested on how to get started with OpenWRT, I'm interested about how to master OpenWRT with Qemu – user1849534 – 2013-01-03T12:30:05.860
Yes sir, I have imagined you had experience with OpenWRT,and for this very reason I voted positively your question, the answer I tried, favoring three links, which allow a general approach and also useful to other users without their knowledge, and also I have focused on answering to your question, "if you can have similar features in emulation", according to my personal experience with routerboards, I have answered it if you can. – RTOSkit – 2013-01-03T16:57:49.893
And in the last link I've provided, you can get your information as set your "TAP" to get good performance in emulation. I guess that you know how to launch a kernel compiled in QEMU, but I do not know if you want to emulate an ARM SoC or an ARM MPU, I hope not to offend your knowledge if I pass a generic link on implementation of an ARM core emulation using QEMU. ...I just try to be helpful
– RTOSkit – 2013-01-03T17:07:36.647